Admitting Ukraine to NATO would mean putting soldiers on Russia's border, and USA and Europe promising to defend Ukraine if invaded. Pres. Biden says that we may admit Ukraine, but we will not defend it with troops until it is admitted.
This is essentially the same as telling Russia to invade Ukraine now, instead of later.
Ukraine is a failed state, and may be better off as part of Russia. USA foreign policy is unbelievably bad. I blame Biden for this war.